1. Field of the Invention
The present invention relates generally to harvesting crop materials and, more particularly, to the selective harvesting of multiple components of such a crop material desirably in a single pass across a crop field with a harvesting machine.
2. State of the Art
In known combine harvesters, a crop or plant material is cut from the field and passed through a threshing and separating mechanism to separate the grain therefrom. The grain, along with other impurities such as, for example, chaff, dust, leaves or other straw particles, is fed to a cleaning mechanism to further clean and separate the grain from such impurities. Such a cleaning mechanism might include one or more sieves with an air stream directed therethrough to assist in the removal of chaff and residual straw.
The grain, now separated and cleaned from the crop material, is collected and temporarily stored in a grain tank located on the combine harvester while the residual material (i.e., material other than grain) is conventionally discharged from the combine harvester back onto the crop field. In some combine harvesters the residual material may be xe2x80x9crethreshedxe2x80x9d such as by recycling it through the threshing and separating mechanism to increase the amount of grain recovered.
The residual materials, such as the straw and chaff, may be discharged from the combine harvester in scattered manner for reintroduction into the soil as a nutrient therefor, or they may be discharged in a narrow row for subsequent collection by another machine. For example, a baler may pass across the field to collect and package (bale) the discharged residual material. However, a conventional baler has no separation equipment associated therewith and packages everything it collects from the field. For example, the baler cannot separate the straw from the chaff. Rather, it consolidates and packages the chaff and the straw along with any other residual material discharged from the combine harvester.
The requirement of returning to the field to collect and package residual material introduces additional time and costs to the harvesting of a given crop. Further, this conventional approach is generally inefficient in the sense that it may be desirable to use some components of the crops as a soil nutrient, while other components may be better suited for other uses. However, as noted above, current baling technologies are xe2x80x9call or nothingxe2x80x9d since they do not offer the ability to further separate the residual material.
One process which attempts to minimize the amount of material which is discharged back to the field is known as the xe2x80x9cMcLeod Harvestxe2x80x9d and is described in U.S. Pat. No. 5,873,226 issued to McLeod on Feb. 23, 1999. The McLeod Harvest threshes the grain in the field and then separates the crop into two portions. The first portion contains substantially all of the straw from the threshed crop and a second portion includes substantially all of the chaff, grain, grain leavings and weed seeds. The first portion is returned to the field during separation while the second portion comprising its various components is transported to a processing plant for separation of the grain from the chaff, grain leavings and weed seeds. The chaff, grain leavings and weed seeds are collectively compacted and crushed in a mill for use as animal feed. The process is purported to increase the amount of grain recovered and to remove weed seeds from the field. The straw is collected in a separate pass over the field as with harvesting with a conventional combine harvester.
One of the principal objectives of the McLeod Harvest is the removal of weed seeds from the crop field. However, the McLeod Harvest process requires a separate mill for separation of the grain from the weed seeds, grain leavings and chaff. Further, the process still requires another pass with a baler to collect the straw as the straw is not the component of a crop conventionally used as a soil nutrient.
As noted above, some uses of the residual material (regardless of the process used to separate the grain therefrom) may provide a farmer with additional revenues from the crop (e.g. by selling the residual materials as animal feed). However, such returns are relatively small and farmers are continually looking to improve such peripheral revenues. Thus, it would be advantageous to target specific revenue generating components of a crop, in addition to the grain, in an effort to increase the return of a given crop. Additionally, it would be advantageous to provide an apparatus and method for selectively harvesting a specified revenue generating component of a crop at substantially the same time as the harvesting of the grain material. For example, it would be advantageous to provide a combine harvester or other machine which provides for the harvesting of at least one additional specified revenue generating component of the plant material, along with the harvesting of the grain, during a single pass over the crop field.
In accordance with one aspect of the invention a method is provided for selectively harvesting multiple components of a plant material. The method includes gathering an amount of plant material from a crop field utilizing a harvesting machine. A grain component is harvested from the plant material and then conveyed to a storage area such as, for example, a storage tank located on or within the harvesting machine. At least one additional plant component is also selectively separated from the plant material. The residual material (i.e., the plant material other than grain and other than the at least one additional plant component) is discharged from the harvesting machine back to the crop field. The at least one additional plant component may be, for example, an internodal stem component of the plant material wherein stem of the plant material is broken adjacent the nodes and the nodes are then separated from the internodal stem portions.
The method may include effecting each of the above steps within the harvesting machine during a single pass across a crop field. In other words, the harvesting machine need not return to the field to effect the selective separation of the at least one additional component of the plant material. Further, the method may include consolidating and packaging the at least one additional plant component, which may also be effected by the harvesting machine if so desired.
In accordance with another aspect of the invention, a method of harvesting a plant material is provided. The method includes gathering an amount of plant material, separating a grain component from the plant material and storing the grain component. The method further includes separating an internodal stem component from the plant material. The internodal stem component may be subsequently consolidated and packaged such as, for example, by a baler. In packaging the internodal stem component, a biodegradable and/or combustible packaging material may be at least partially wrapped about a consolidated mass of the internodal stem component.
Another aspect of the invention comprises a harvesting machine. The harvesting machine includes a primary threshing and separating mechanism configured to separate a grain component from a plant material. A secondary threshing and separating mechanism is configured to selectively separate at least one additional component from the plant material. For example, the secondary threshing and separating mechanism may be configured to break a stem component of the plant material at a location adjacent a node of the stem component and then separate the node therefrom. The node and the resulting internodal stem component may then be separated from one another.
The harvesting machine may further include additional cleaning and separating mechanisms such as, for example, sieves, associated with the cleaning of the grain component, the at least one additional component, or both.
Further, the harvesting machine may include a packing mechanism positioned and configured to receive the at least one additional component from the secondary threshing and separating mechanism. The packaging mechanism may be configured to consolidate and package the at least one additional component for subsequent use.
Another embodiment of the present invention encompasses a harvesting system. The harvesting system includes a harvesting machine having a primary threshing and separating mechanism configured to separate a grain component from a plant material. A secondary threshing and separating mechanism is configured to selectively separate at least one additional component from the plant material. A packing mechanism is configured to receive the at least one additional component from the secondary threshing and separating mechanism. The packaging mechanism may be operatively associated with a secondary vehicle. The secondary threshing and separating mechanism may be operatively associated with the harvesting machine or, alternatively, with the secondary vehicle. Such a secondary vehicle may be mechanically coupled to, and pulled by, the harvesting machine.